vo: why won't romney level with us about his tax plan, which gives the wealthy huge new tax breaks? because according to experts, he'd have to raise taxes on the middle class - or increase the deficit to pay for it. if we can't trust him here... how could we ever trust him here? >>> i'm wolf blitzer. here's a look at what's ahead in the next couple of hours. we're learning new details on what the vice president joe biden is doing to prepare for tomorrow night's debate. also, our john king is focusing in on a key group of ohio voters who could decide the election. and forg funding big bird. what about joe biden's favorite ride? we're talking amtrak. we'll explain. stand by. you're in "the situation room." >>> with just 27 days to go until the election, democrats say mitt romney is running to the political center as fast as he can. among other things, they're pointing to romney's comments today about abortion. here's a quick snapshot. >> mitt romney said "there's no legislation with regards to abortion that i'm familiar with that would become part of my agenda." and that statement doe